AC power sockets and power plugs have been a part of people's everyday life for decades. AC power sockets and power plugs are devices that allow electrically operated equipment to be connected to a primary AC power supply. As an AC power socket may contain one or more plug components connecting to a primary AC power supply, an AC power socket as used in this specification may contain one or more functions of a power plug. In other words, an AC power socket in this specification may function as a power plug.
A power socket generally contains two or three electrical conductors for an electrically operated device to connect (usually through a power plug at the electrically operated device side). For a power socket containing three electrical conductors, the three electrical conductors are often referred to as the live conductor, the neutral conductor, and the grounding conductor. For a power socket containing two electrical conductors, the electrical conductors are the live conductor and the neutral conductor. A neutral conductor is usually at or very near to earth potential. A live conductor carries the full supply voltage relative to the neutral, and it is also called a line/phase/hot conductor. A grounding conductor allows the exposed metal parts of the electrically operated device to be connected to earth (known as grounding). The electrical conductors have corresponding receptacles, slots or holes (called female) at the power socket for the electrically operated device to connect through protruding prongs, blades, or pins (called male) of a power plug.
Power sockets may be fixed on a building structure and connected to an energized electrical circuit. These power sockets are often called wall power sockets or wall socket. Power sockets may be mobile and contain one or more plugs to connect to a wall socket, and these power sockets are often called cubical power sockets (or simply cubical sockets) as the shape of such power sockets is often cubical with a square or substantially square shape at six sides of such power sockets. Yet, other shapes for these mobile power sockets are possible. Persons of ordinary skill in the art know that cubical socket may take a different shape other than cubical such as prism and cuboid that contain six sides. The specification refers all such mobile power sockets containing six sides as cubical sockets. It is challenging to build a cubical socket that is compact, economic, and complying with international/national rules/regulation on safety.